Vitamin B12 (cobalamin), a cobalt-containing water-soluble vitamin, serves as an important cofactor for many enzymatic reactions in mammals that are required for normal cell growth, function and reproduction, nucleoprotein and myelin synthesis, amino acid metabolism, and erythropoiesis. Cobalamin is required for folate utilization; B12 deficiency can cause functional folate deficiency. Unlike humans, macrocytic anemias do not appear to be a significant component to cobalamin deficiency in dogs or cats. Clinical signs associated with cobalamin deficiency in cats may include weight loss, poor haircoat, vomiting, or diarrhea. Increases in serum methionine and methylmalonic acid, and decreased serum cystathionine and cysteine values may be noted. Homocysteine levels do not appear to be affected. In dogs, cobalamin deficiency may cause or contribute to inappetance, diarrhea, weight loss, leukopenia, or methylmalonylaciduria. In ruminants, vitamin B12 appears to be synthesized by rumen microflora and requires dietary cobalt to be present for its forma cyanocobalamin (vitamin b12) 233 tion. Clinical signs seen with cobalamin deficiency states associated with cobalt deficiency in cattle and sheep include inappetance, lassitude, poor haircoat/fleece, poor milk production, weight loss, or failure to grow.
Cyanocobalamin is used for treating deficiencies of vitamin B12. Malabsorption of the nutrient secondary to gastrointestinal tract disease, or dietary chromium deficiencies (in ruminants) can be associated with dietary deficiencies of vitamin B12. As there appears to be a high percentage of cats with exocrine pancreatic insufficiency or gastrointestinal disease that are deficient in cobalamin, there is considerable interest in evaluating serum cobalamin (vitamin B12) in these patients. Giant schnauzers may have a genetic defect affecting the location of the cobalamin-intrinsic factor, causing cobalamin deficiency. Dogs with inflammatory bowel disease may also develop cobalamin deficiency.
劑量數字暫停提供：VetPro 的劑量改依 DRUGAPI 藥物資料庫對外的內容，DRUGAPI 目前不提供可直接計算的劑量。下方列出 DRUGAPI 的審查結論與劑量審查引用的來源；計算機可手動輸入劑量換算。
D0774 與 D0686 是同一 cyanocobalamin 概念；D0686 是唯一已複核臨床條目。D0774 必須導向 D0686，不得計算、處方或另行提供第二套劑量、安全、交互作用、產品及飼主資料。
DRUGAPI 劑量審查引用的獸醫官方標示（各標示只適用於其產品、物種與法域，不可互換）
依出現頻率分組；嚴重副作用獨立列出，臨床上需立即辨識。